Genesis 8:10

10. Yet other seven days Here and in Genesis 8:12 is a clear allusion to the sevenfold division of time, the week, a period which was adopted by all the Shemitic races, by the Egyptians, by the Chinese and Hindus as far back as authentic history extends, and which was even found among the ancient Peruvians . Unlike the year, the month, the day, this division does not correspond with any natural phenomena, and can only be reasonably accounted for by supposing it to be a traditional remembrance of the creative week . It is probable that Noah, on the Sabbath, sent forth the raven and the dove, in earnest prayer seeking providential aid and guidance. These weekly waitings from Sabbath to Sabbath were additional trials to his faith.